Iphone Incurring Data Charges Whilst Connected To Wifi ?

[sezzi1]

I have an iPhone 3g which has been unlocked and jailbroken, I've just put a Vodafone PAYG Sim in it and everything works ok except that Vodafone keeps charging me a £1 a day for going online when it's already connected to my home wifi [which is with Talk Talk]. There are no settings set up in the Cellular Data Network settings, all boxes are blank and data roaming is switched off so I'm confused why I keep getting charged. Before putting the Vodafone sim in the phone I used it with my Orange Sim and never incurred charges when connected to my home wifi so has Vodafone different settings ? I did phone them to query why my phone credit was disappearing and they told me that even if I was connecting to the internet through my home wifi I would still be charged £1 a day for doing this, surely this isn't right, any help

 

[mpw2081]

does not sound right to me mate

 

[Toshman]

Sometimes wifi goes to sleep when the phones is in standby in which case the phone may be connecting to the cellular network, any background syncing will then incur data charges. Also, if you are receiving any MMS this might be happening over cellular data.

My S2 was doing this until I went into settings and told the wifi not to sleep.